dnl	$OpenBSD: prep,v 1.17 2014/02/28 00:47:14 afresh1 Exp $
To be able to boot the OpenBSD/MACHINE installation program, you will need
to learn a bit about RedBoot, the low-level process that controls the
microprocessor after hardware initialization.
The enabled features between IOData HDL-G and Thecus N2100 vary, so
different methods will be needed on both machines.

All these machines use RedBoot as their firmware and boot loader interface,
with varying limitations.  Thecus systems cannot load a file from disk, but
can load an image from flash or network.  IOData systems however are more
restricted, and can only load an image from ext2fs partitions on disk, while
the commands to load from flash are not available, and network booting does
not appear to work.

Thecus N2100 setup:

	Talking to the Thecus

	The Thecus N2100 needs a serial cable. On the back of the disk drive
	circuit board, there is either a 10-pin header (with one pin removed),
	or 9 holes for you to solder in your own header.  The ribbon cable
	that connects from there to your serial cable or the serial port on
	your computer is of the same type as used on older i386 PCs, but
	be aware that there are two different types of 10-pin IDC to DB-9M
	ribbon cable in use, which look identical (the differences are hidden
	inside the DB-9 connector). The cable you need is wired using the
	"AT-Everex" or "Asus" pinout, as described here:

	    http://www.pccables.com/07120.htm

	and *not* the more straightforward to solder "crossed" type:

	    http://www.pccables.com/07121.htm.

	If you wish to check a cable, or make your own, the pinouts are:

	    DB9           IDC10
	    ===           =====
	    1 2 3 4 5     1 3 5 7 9
	     6 7 8 9      2 4 6 8 10

	Wire pin 1 to 1, 2 to 2 etc, with 10 not connected.

	On the Thecus N2100, it is also necessary to move jumper J3 to J4 to
	properly route the serial port interrupt to allow serial to work under
	OpenBSD. This jumper is located under the disk drives, so you may wish
	to ensure its correct setting while you are installing the disk(s).
	For instructions on assembling/disassembling your N2100, see the N2100
	Manual at
	    http://www.thecus.com/download/manual/N2100%20UM%20EN.pdf


	Booting Thecus N2100

	When you have connected your computer, a command such as
       	"cu -l cuaU0 -s 115200" (assuming cuaU0 is your serial port device)
	should connect you to the Thecus console. Now apply power to the
	Thecus and start it.

	After some device probe information, you should see this prompt:

	    == Executing boot script in 3.000 seconds - enter ^C to abort

	To enter interactive RedBoot, it is necessary to press ^C within the
	given number of seconds of the prompt. It will typically accept the
	^C if typed during the diagnostics that precede this prompt.

	The recommended way to boot OpenBSD on Thecus is to configure
	networking and load bsd.rd from a TFTP server or HTTP server.

	Update the IP address, netmask and server address with the commands
	listed below to allow booting from the network. TFTP and HTTP are
	supported. (BOOTP configuration _may_ not work)

	Using ip_address only allows you to set the local IP address and
	the IP address of the server where bsd.rd is located.  This command
	takes effect immediately but will not persist across a reboot.

	    RedBoot> ip_address -l 10.0.0.21 -h 10.0.0.7
	    IP: 10.0.0.21/255.255.255.0, Gateway: 0.0.0.0
	    Default server: 10.0.0.7, DNS server IP: 0.0.0.0

	Once you have done this, and have set up your TFTP server on
	the gateway machine (10.0.0.7 in the above example), you can
	boot manually.

	    RedBoot> load /bsd.rd
	    Using default protocol (TFTP)
	    Entry point: 0x00200000, address range: 0x00200000-0x0066a49c
	    RedBoot> go

	Once OpenBSD is installed on the hard disk, you will only need to
	load the OpenBSD/MACHINE boot loader (/boot) the same way, and just
	hit "return" to boot OpenBSD.


	Automatic Booting

	However, for easier booting, you may wish to store the OpenBSD boot
	loader in the flash memory, so that the Thecus will boot automatically
	into OpenBSD when it is powered up.
	Doing so disables the devices' built-in Linux kernel, however, and
	makes it difficult or impossible to apply future RedBoot firmware
	upgrades. There are two general approaches:
	1) Just change the boot configuration (using 'fconfig') to automate
	   the above booting (your TFTP or HTTP boot server will still be
	   needed).
	2) Remove a file from the flash and replace it with OpenBSD's /boot;
	   this configuration can then be booted standalone.

	Thecus RedBoot provides the 'fconfig' (not ifconfig) command to
	change the boot configuration of the device. Also 'fis' is provided
	to perform flash operations.

	Due to a change made by Thecus to the firmware, fconfig does not
	work with Thecus firmware version "1.93 (Feb 2007)" or later, and
	*it is thus not possible to make the Thecus auto-boot into OpenBSD*
	(worse, it will let you enter the "script" commands below, but
	ignore them on boot). To correct this, you must "upgrade" your
	Thecus down to firmware version "1.93 Nov 29 2005" using the file 
	n2100-downgrade-reboot.rom *before* you remove any files from flash.
	You can get this file from Thecus; they have given permission for
	it to be mirrored at
	    http://www.darwinsys.com/openbsd/thecus.html
	However, if you have removed files from flash before running this
	downgrade, it is not believed to be possible to get your machine
	to auto-boot.

	Once the downgrade is done, if your TFTP machine will always be
	around, you can autoboot just by changing the boot script with
	fconfig, as follows: (in this example, 192.168.1.254 is both the
	default IP gateway and also the TFTP server):

	    RedBoot> fconfig
	    Run script at boot: true
	    Boot script: 
	    .. load /boot.armish
	    .. go
	    Enter script, terminate with empty line
	    >> load /boot.armish
	    >> go
	    >> 
	    Boot script timeout (1000ms resolution): 3
	    Use BOOTP for network configuration: false
	    Gateway IP address: 192.168.1.254
	    Local IP address: 192.168.1.253
	    Local IP address mask: 255.255.255.0
	    Default server IP address: 192.168.1.254
	    Console baud rate: 115200
	    DNS server IP address: 
	    GDB connection port: 9000
	    HW Status: 0
	    Force console for special debug messages: false
	    MAC address: 0x00:0x14:0xFD:0x30:0x25:0x14
	    MAC address 2: 0x00:0x14:0xFD:0x30:0x25:0x15
	    Network debug at boot time: false
	    Reset default: Normal
	    Serial number: N2100 V2.1.06
	    ... Unlock from 0xf0fc0000-0xf0fc1000: .
	    ... Erase from 0xf0fc0000-0xf0fc1000: .
	    ... Program from 0x07fd2000-0x07fd3000 at 0xf0fc0000: .
	    ... Lock from 0xf0fc0000-0xf0fc1000: .
	    RedBoot> 

	This configuration can easily be set back to the default, as the
	Linux system does not get erased from the flash memory. To set it
	back, just change the boot script with fconfig back to what it was,
	for example:

	    thecus_setip
	    fis load ramdisk
	    fis load kernel
	    exec -c "console=ttyS0,115200 root=/dev/ram0 initrd=0xa0800000,42M mem=128M@0xa0000000"

	You could also remove the boot script altogether by not re-entering
	it, so you would be dropped to the RedBoot shell by default.

	Recheck the new values and issue the 'reset' command.

	For the standalone booting option, you will have to load /boot into
	the flash memory. To overwrite the Thecus ROM behaviour, it is
	necessary to delete a 'rom file' and load the OpenBSD bootloader image
	there.  With networking configured (as above), remove a region and
	load the 'boot' program.

	Initially the machine will contain much like the following:

	    RedBoot> fis list
	    Name              FLASH addr  Mem addr    Length      Entry point
	    RedBoot           0xF0000000  0xF0000000  0x00040000  0x00000000
	    RedBoot config    0xF0FC0000  0xF0FC0000  0x00001000  0x00000000
	    FIS directory     0xF0FE0000  0xF0FE0000  0x00020000  0x00000000
	    ramdisk           0xF0040000  0x00800000  0x00D00000  0x00800000
	    kernel            0xF0D40000  0x00200000  0x00160000  0x00200000
	    user              0xF0EA0000  0xF0EA0000  0x00120000  0x00200000

	There is no free space in the rom for the 'boot' program, so something
	must be removed. 
	WARNING: this will make the machine unbootable into the original
	Thecus server mode and it is quite difficult to restore to the
	original software.
	EXTREME WARNING: Do not touch the RedBoot, RedBoot config, or FIS 
	directory regions, as doing so will probably brick the device.

	Remove (with confirmation) a region to make space, eg 'user' (the
	non-root files needed to run Linux from Flash Memory).

	    RedBoot> fis delete user
	    Delete image 'user' - continue (y/n)? y
	    ... Erase from 0xf0ea0000-0xf0fc0000: .........
	    ... Unlock from 0xf0fe0000-0xf1000000: .
	    ... Erase from 0xf0fe0000-0xf1000000: .
	    ... Program from 0x07fdf000-0x07fff000 at 0xf0fe0000: .
	    ... Lock from 0xf0fe0000-0xf1000000: .

	Load the OpenBSD/MACHINE bootloader 'boot' via TFTP or HTTP:

	    RedBoot> load -m http /boot
	    Entry point: 0x00100000, address range: 0x00100000-0x001067e0

	Save that loaded file to flash:

	    RedBoot> fis create boot
	    ... Erase from 0xf0ea0000-0xf0ec0000: .
	    ... Program from 0x00100000-0x001067e0 at 0xf0ea0000: .
	    ... Unlock from 0xf0fe0000-0xf1000000: .
	    ... Erase from 0xf0fe0000-0xf1000000: .
	    ... Program from 0x07fdf000-0x07fff000 at 0xf0fe0000: .
	    ... Lock from 0xf0fe0000-0xf1000000: .

	Confirm its addition:

	    RedBoot> fis list
	    Name              FLASH addr  Mem addr    Length      Entry point
	    RedBoot           0xF0000000  0xF0000000  0x00040000  0x00000000
	    RedBoot config    0xF0FC0000  0xF0FC0000  0x00001000  0x00000000
	    FIS directory     0xF0FE0000  0xF0FE0000  0x00020000  0x00000000
	    ramdisk           0xF0040000  0x00800000  0x00D00000  0x00800000
	    kernel            0xF0D40000  0x00200000  0x00160000  0x00200000
	    boot              0xF0EA0000  0x00100000  0x00020000  0x00100000

	Now that the bootloader is in place, update fconfig to autoboot
	OpenBSD:

	    RedBoot> fconfig
	    Run script at boot: true
	    Boot script:
	    .. fis load ramdisk
	    .. fis load kernel
	    .. exec ...
	    Enter script, terminate with empty line
	    >> fis load boot
	    >> go
	    >>
	    Boot script timeout (1000ms resolution): 1
	    ...
	    Update RedBoot non-volatile configuration - continue (y/n)? y
	    ... Unlock from 0xf0fc0000-0xf0fc1000: .
	    ... Erase from 0xf0fc0000-0xf0fc1000: .
	    ... Program from 0x0ffd2000-0x0ffd3000 at 0xf0fc0000: .
	    ... Lock from 0xf0fc0000-0xf0fc1000: .

	The important part is that 'Run script' is true and that the commands
	are 'fis load boot' followed with 'go' ('boot' being the file created
	by 'fis create boot' earlier). Confirm the update and type 'reset'
	to auto boot.

	The bootloader is command driven with timeout like many other OpenBSD
	architectures.


IOData HDL-G setup:

	The hda1 partition is the boot partition for Linux; it contains
	zImage and initrd. Since RedBoot on this machine can only boot from
	the ext2fs partition, it is very important that this partition be
	preserved and not be reformatted. If this partition is destroyed, it
	will be necessary to remove the disk drive and recreate the partition
	on another machine. (RedBoot should be able to boot from the network,
	however that has been unsuccessful on IODATA HDL-G so far)

	To install OpenBSD, boot linux, and copy 'boot' and 'bsd.rd' into the
	partition mounted on /dev/hda1. After that has been done, it is
	possible to reboot into OpenBSD and install the device. Installation
	can then proceed as on other machines, however care must be take to
	not remove wd0i/hda1 partition (fdisk partition 0). DO NOT chose the
	'full disk installation' option.

	Unfortunately, since IODATA did not provide the 'fconfig' command, it
	is not possible to change the boot commands run when RedBoot starts,
	thus it not possible to autoboot OpenBSD; the OpenBSD/MACHINE
	bootloader is currently unable to work when loaded as `zImage'.
	Futhermore, to disable autobooting into Linux, at least one of the
	zImage and initrd files need to be renamed or removed.  This can be
	done from the shell in bsd.rd.

	To load the ramdisk kernel to install use the commands

	    RedBoot> load -m disk hda1:/bsd.rd
	    RedBoot> go

	to boot normally, load the bootloader which will give options to boot
	other kernels.

	    RedBoot> load -m disk hda1:/boot
	    RedBoot> go

	Since this bootloader is able to boot any kernel from the OpenBSD
	root partition, it is not necessary to keep bsd.rd on the hda
	partition after OpenBSD is installed.
